The United Nations refugee chief on Thursday called on Pakistanis not to hold Afghan refugees responsible for terrorism in their country, amid growing public calls for their deportation and worsening relations between the two neighbors.

U.N. High Commissioner for Refugees Filippo Grandi warned that the roughly 2.5 million Afghan refugees in Pakistan are slowly becoming a “forgotten” crisis, and called on the international community to invest more funds to help them.

“My appeal is that, not only to the authorities but also to the local population: refugees as you know are not terrorists,” Grandi said during a visit to a repatriation centre outside the northwestern Pakistan city of Peshawar.

Pakistani officials have recently implied the possibility of deporting Afghan refugees, amid tense relations with Kabul.

On Monday, Sartaj Aziz, Pakistan’s foreign policy chief, told a Pakistani television channel that Afghan refugee camps had become “safe havens for terrorists”.

On Wednesday, Pakistani federal minister Abdul Qadir Baloch warned that Pakistan was not willing to host Afghan refugees indefinitely.

A decision to renew their legal status by June 30 has not yet been announced, although past deadlines have been extended at the last minute.

The number of Afghans voluntarily returning home slumped this year as violence aggravated in Afghanistan, where the government and its U.S. allies have been fighting a stubborn Taliban insurgency.

So far, about 6,000 Afghans have chosen to return home from Pakistan in 2016, compared with 58,211 voluntary repatriations last year, according to the UNHCR.

At the repatriation centre, refugees waited in sweltering heat for their cases to be processed, a necessary step before they can set off on the journey home.

Many Afghan refugees say they are being pressured to go back by the authorities, amid worsening diplomatic relations between Afghanistan and Pakistan.